Weft detector device



Aug. 17, 1965 w, J. KOYDER ETAL 0,

' WEFT DETECTOR DEVICE Filed Feb. 28, 1963 W41 76/? J. KOYDER BY @fi/APD M4 PH/ZZ/PS INVENTORS ATIUFNEV United States Patent Ofitice 3,Z0,85.3 Patented Aug. 17, 1965 3,200,853 WEFT DETECTOR DEVICE Walter J. Koyder and Richard W. Phillips, Meadviile, Pa, assignors to Talon, Inc., a corporation of Pennsylvania Fiied Feb. 28, 1963, Ser. No. 261,772 Claims. (Cl. 139--37) This invention relates to stop motions for looms, particularly needle looms, wherein a multiplicity of warp threads or yarns are adapted to be drawn or pulled into and through the loom under uniform tension from a source of supply by means of take-up mechanism positioned at the delivery side of the loom.

The present invention relates particularly to a device for detecting the absence of a weft thread in the woven fabric when it is delivered from the loom which weft thread is normally adapted to'be interwoven with the warp threads as they pass into and through the loom in a manner Well known to those skilled in the art.

In the weaving of narrow fabrics such as tapes and the like, it is the general practice to provide a knitted edge along one edge of the fabric which is accomplished by a reciprocating knitting needle arranged along side of the warp threads which engages loops of the Weft thread as they are projected into the shed between the warp threads by a filler or weft needle in a well known manner. After a period of use sometimes these knitting needles break or become damaged or for some reason the weft thread will break but the loom will continue to operate thereby resulting in providing a length of fabric without a weft thread knitted therein. Heretofore, this would be discovered only upon inspection of the fabric-by the operator. Accordingly, it will be seen that this resulted not only in a waste of material but decreased the efficiency of the loom in that a completed fabric was not being woven. It is to a device for de tecting the lack of the interweaving of the weft threads with the warp threads to which this invention relates.

Accordingly, it is the general object of the present invention to provide an improved device for detecting the absence of the weft thread in a fabric immediately after the fabric leaves the weaving station, and which is particularly adapted to initiate easily and quickly the actuation of an electrical stop motion.

It is another object of the invention to provide an improved detector device which is simple and inexpensive in its construction and, at the same time, efilcient and effective in its use.

It is a more specific object of this invention to provide a detector device having a feeler finger incorporated therewith which rests normally on the fabric at the takeup mechanism of a loom and which cooperates with the feed roll of the mechanism to stop the loom in the absence of a Weft thread in the fabric in the vicinity of the feeler finger.

It is a further object of the invention to provide an improved detector device consisting of a minimum number of inexpensive parts which can be conveniently assembled and incorporated with existing looms.

Various other objects and advantages of this invention will be more apparent in the course of the following specification, and will be particularly pointed out in the appended claims.

In the accompanying drawings, there is shown for the purpose of illustration, an embodiment which the invention may assume in practice.

In these drawings:

FIG. 1 is a top View of the tape take-up mechanism of a loom showing the weft detector device in accordance with the present invention incorporated therewith.

FIG. 2 is a front elevational view,

FIG. 3 is a sectional view taken on line 3-3 of FIG. 1, and

FIG. 4 is an enlarged fragmentary perspective view of the weft detector device of the present invention.

Referring more particularly to the drawings, there is shown the front wall L at the delivery end of a needle or shuttleless loom of the type disclosed in the patent to Osborne Firing et al., No. 2,497,077, issued February 14-, 1950, with which the present invention is adapted to be incorporated.

At the delivery end of the loom, there is arranged in a bracket 2 on the front wall L of the loom, a shaft 3 on which there is rotatably mounted a take-up roll 4- which is adapted to receive a loop of a woven tape T as it is delivered from the loom with which the improved weft-detector device in accordance with the present invention is incorporated.

This weft detector consists of a plate-like supporting member 40 which is made preferably of a suitable nonconducting material, having the lower end thereof attached to the outer end of the shaft 3, as more clearly shown in FIGS. 1 and 2 of the drawings. In the upper end of this member 40, there is arranged a stud shaft 5 which is rotatable relative thereto so as to provide a rocking action.

On the inner end of this shaft 5, there is secured thereto, a Weighted body member 6 which is positioned above and directly opposite the take-up roll 4.. Weighted body member 6, pivotally mounted to shaft 5 adjacent one of its ends, is normally urged by the force of gravity acting thereon to move towards the periphery of roll 4 in a fixed plane, which is substantially transverse to the axis of shaft 5. The lower side of this Weighted member 6 is preferably arcuated, as at 7, so as to correspond to the periphery of the roll 4 upon which it rests and with which it cooperates. As best shown in FIGS. 3 and 4, the configuration of weighted body member e is such that the greater portion of its mass is located adjacent to its remote free end, which is opposite to the end at which it is mounted to shaft 5.- On the inner lower edge of this weighted member and to the inner side of this arcuated portion 7, there is mounted a relatively thin feeler finger 8 which is acted upon by the mass of body member 6 such that finger 8 will cooperate with the periphery of the roll 4 to complete an electric circuit in the absence of any material on the roll in a manner and for a purpose hereinafter to be described. Finger 8, which is located intermediate the center of gravity of body member 6 and the axis about which body member 6 pivots, thus receives the downward thrust of body member 16. Therefore, because of the mechanical advantage, the force applied to finger ii is greater than the gravitational force acting upon the center of gravity of body member 6.

On the outer end of the shaft 5, there is arranged an electrical connection 9 on the end of a wire 10 which in turn is connected to an electrical circuit for controlling the operation of the loom.

The Weft detector device of the present invention functions in the following manner. It will he understood that the feeler finger 8, normally rides on top of the tape T adjacent to its knitted edge opposite the take-up roll 4 as the tape is delivered from the loom and is normally being woven, as shown in FIG. 3. In the event that the weft yarn is missing or for some reason breaks this feeler finger will pass between the warp yarns adjacent the knitted edge of the tape due to the take-up roll 4 so as to the connection 9 and the wire 10 to stop the loom ima 3 mediately. The weft yarn is then properly replaced in the loom mechanism for Weaving and the loom is again set in operation.

As a result of this invention, it will be seen that this simple Weft detecting device eliminates the necessity of complicated detecting mechanism and that such a device can easily and conveniently be incorporated with existing looms at a minimum cost and also increases the number of looms which can be operated by a single operator.

While there is shown and described an embodiment which the invention may assume in practice, it will be understood that this embodiment is merely for the purpose of illustration and description, and that other forms may be devised within the scope of the invention as defined in the appended claims.

What we claim as our invention is:

1. In combination with take-up mechanism for a loom having a take-up roll rotatably mounted at the delivery end thereof:

a breakage detector comprising a weighted body member mounted to a shaft for pivotal movement thereabout,

said shaft supported at spaced apart points such that said body member is normally urged by gravity to move in a fixed plane about said shaft and towards the periphery of said roll,

a feeler finger carried by said body member intermediate said shaft and the center of gravity of said body member for riding normally on the surface of a woven fabric moving over said roll, and which has a knitted edge,

said feeler finger having a thickness which is less than the distance between any two adjacent warp threads of the woven fabric for entering the space there between to ride on the upper surfaces of the Weft threads of the woven fabric as it moves over the roll, and

a normally open electric circuit including said feeler finger and said take-up roll for maintaining said loom in an operating condition when properly woven fabric is normally disposed on said take-up roll,

, said feeler finger is movable through a fixed plane substantially perpendicular to the axis of said shaft such that said feeler finger is maintained between the same two continuous warp threads by a force 4 greater than the gravity force exerted at the center of gravity of said body member and is maintained in contact with successive weft threads of said woven fabric moving over said roll for closing said electrical circuit to render said loom inoperative in the absence of a weft thread.

2. The combination as defined in claim 1 wherein said body member includes an arcuate bottom surface having a surface configuration which is complemental to the peripheral surface of said roll, the upper surface of said body member extending in a direction substantially divergent to said bottom surface such that the center of gravity of said body member is located adjacent its free end.

3. The combination as defined in feeler finger is mounted to one side of said Weighted body member and projecting downwardly below the bottom surface of said weighted body member a distance greater than the thickness of a woven fabric moving over said take-up roll.

4. The combination as defined in claim 3 wherein said weighted body member is disposed adjacent the knitted edge of said woven fabric and over the end portion of said take-up roll and continuous warp threads adiacent said knitted edge for sensing the absence of one or more weft threads.

5. The combination as defined in claim 1 wherein said feeler finger is mounted adjacent said shaft and intermediate said shaft and said center of gravity of said body member whereby the force exerted on said feeler finger to maintain said feeler finger in contact with said woven fabric is greater than the force of gravity acting on said body member.

References Cited by the Examiner UNITED STATES PATENTS 2,168,755 8/39 Wachsman 66166 2,321,482. 6/43 Hadley 26-17 2,674,277 4/54 Siciliano 139-370 3,104,683 9/63 Weiner l39-124.1 FOREIGN PATENTS 784,654 10/57 Great Britain DONALD W. PARKER, Primary Examiner. MERVIN STEIN, Examiner.

claim 1 wherein said said feeler finger rides between two 

1. IN COMBINATION WITH TAKE-UP MECHANISM FOR A LOOM HAVING A TAKE-UP ROLL ROTATABLY MOUNTED AT THE DELIVERY END THEREOF: A BREAKAGE DETECTOR COMPRISING A WEIGHTED BODY MEMBER MOUNTED TO A SHAFT FOR PIVOTAL MOVEMENT THEREABOUT, SAID SHAFT SUPPORTED AT SPACED APART POINTS SUCH THAT SAID BODY MEMBER IS NORMMALLY URRGED BY GRAVITY TO MOVE IN A FIXED PLANE ABOUT SAID SHAFT AND TOWARDS THE PERIPHERY OF SAID ROLL, A FEELER FINGER CARRIED BY SAID BODY MEMBER INTERMEDIATE SAID SHAFT AND THE CENTERR OF GRAVITY OF SAID BODY MEMBER FOR RIDING NORMALLY ON THE SURFACE OF A WOVENN FABRIC MOVIN OVER SAID ROLL, AND WHICH HAS A KNITTED EDGE, SAID FEELER FINGER HAVING A THICKNESS WHICH IS LESS THAN THE DISTANCE BETWEEN ANY TWO ADJACENT WARP THREADS OF THE WOVEN FABRIC FOR ENTERING THE SPACE THEREBETWEEN TO RIDE ON THE UPPER SURFACES OF THE WEFT THREADS OF THE WOVEN FABRIC AS IT MOVES OVER THE ROLL, AND A NORMALLY OPEN ELECTRIC CIRCUIT INCCLUDING SAID FEELER FINGER AND SAID TAKE-UP ROLL FOR MAINTAINING SAID LOOM IN AN OPERATING CONDITION WHEN PROPERLY WOVEN FABRIC IS NORMALLY DISPOSED ON SAID TAKE-UP ROLL, SAID FEELER FINGER IS MOVABLE THROUGHH A FIXD PLANE SUBSTNATIALLY PERPENDICULAR TO THE AXIS OF SAID SHAFT SUCH THAT SAID FEELER FINGER IS MAINTAINED BETWEEN THE SAME TWO CONTINUOUS WARP THREADS BY A FORCE GREATER THAN THE GRAVITY FORCE EXERTED AT THE CENTER OF GRAVITY OF SAID BODY MEMBER AND IS MAINTAINED IN CONTACT WITH SUCCESSIVE WEFT THREADS OF SAID WOVENN FABRIC MOVING OVER SAID ROLL FOR CLOSING SAID ELECTRICAL CIRCUIT TO RENDER SAID LOOM INOPERATIVE IN THE ABSENCE OF A WEFT THREAD. 